Collapsible containers for liquids



Oct. 11, 1955 v. H. HASSELQUIST 2,719,932

COLLAPSIBLE CONTAINERS FOR LIQUIDS Filed Nov. 24, 1950 j 5 wafaa fi-ig.527470%? United States latent Oflice 2,719,982 Patented Oct. 11, 1955COLLAPSIBLE CONTAINERS FOR LIQUIDS Victor H. Hasselquist, Akron, Ohio,assignor to The B. F. Goodrich Company, New York, N. Y., a corporationof New York Application November 24, 1950, Serial No. 197,498

6 Claims. (Cl. 4177) This invention relates to collapsible containersfor liquids and is especially useful in the manufacture of portablewading and swimming pools, although the invention is also useful incontainers for storing liquids, such as, wash tubs, stock-water tanks,and tanks for similar purposes.

In my Patent No. 2,529,872 a collapsible container is shown in which aflat bottom is united to a normally flat marginal wall, the wall beingof double-walled construction and being inflatable so that the upperedge of the marginal Wallis held above the liquid in the container bythe buoyance of the rim which floats upon the surface of the liquid inthe container. In the manufacture of such containers of large dimensionit has been found desirable to stilfen the inflatable rim portion by theuse of an inner .tube inserted within the doublewalled portion of themarginal wall. Such a construction permits use of a relatively stiffinner tube which may be inflated to a higher pressure than would bepermitted with a single walled container and the inner tube providesagainst leakage of air. It has been found, however, that a container ofthat type has presented difficulties of manufacture and in case ofinjury to the inner tube, the tube could not be removed for repairwithout disturbance of the container. Furthermore, the thin rubber-likematerial comprising the marginal wall of the container was subject toleaks due to fine pin holes in the material and under hydrostaticpressure of the liquid within the container filling of the sidewall withliquid would occur at times which liquid has been inconvenient toremove. Furthermore, the stiifness of the inner tube made it diflicultto fold such a container containing the tube in a small space forstorage.

It is an object of the present invention to overcome the foregoing andother difliculties by providing a container of this type in which accessto the inner tube may be conveniently eflected or in which the innertube may be readily removed for repair purposes or storage of thecontainer.

Other objects are to provide for constant drainage of liquid frombetween the double-walled structure of the sidewalls, such asnecessitated by insignificant slow leaks at the inner layer of thesidewall; to provide for an access opening at the bottom of thecontainer; to provide self-restraining of the outer layer of thesidewall while permitting drainage of the sidewall; to provide efiectivemarginal reinforcement of the top of the sidewall; to stabilize thecontainer when placed upon sloping surfaces, and to provide for storageof the container in a minimum of space.

These and other objects will appear from the following description andthe accompanying drawings.

Of the drawings,

Fig. 1 is a perspective view of the filled container in use.

Fig. 2 is a sectional view taken on line 22 of Fig. 1.

Fig. 3 is a plan view of the inner tube.

Fig. 4 is a sectional view of the superimposed layers of sheet materialassembled in the position of the layers in the article, but spaced fromeach other to show their relative arrangement and before they are seamedtogether.

Fig. 5 is a sectional view of the container with the parts of Fig. 4 inassembled and seamed relation, the flattened container being shown infull lines, and the position of the outer layer when assembling theinner tube with the other parts of the container being indicated by dotand dash lines.

Referring to the drawings, the container has a flat bottom 10 offlexible impervious sheet material, preferably of circular form. To themargin of the bottom 10, the marginal wall 11 is secured by an inwardlyturned marginal seam 12. The marginal wall comprises an inner layer 13,an outer layer 14, and a restraining band 15, united to each other as byan inwardly directed seam 16, which joins the inner layer 13 and outerlayer 14 to each other and in an inwardly directed seam 17 uniting theouter layer 14 to the restraining band 15. All of these parts of thecontainer are formed of flat material as indicated in Fig. 4, theportions 13, 14, and 15 being in the form of fiat rings. While it ispossible to make each of these parts from a single sheet of materialeach of them may be made by piecing together strips or segments ofmaterial as desired.

Between the inner layer 13 and the outer layer 14 of the marginal wall,an inner tube 20 is inserted. The tube may be of rubber or otherrubber-like material suitable for holding air at low pressure and it ispreferred to make this tube of butyl rubber which is highly impervious.The tube 20 has a valve stem 21 whereby it may be inflated by anysuitable means (not shown) such as by a bicycle pump or an air line. Thevalve stem 21 is made to extend through the marginal wall of thecontainer but may be contained in the pocket which houses the innertube. For retaining the outer marginal layer 14 in position, therestraining band 15 has its inner margin hemmed too, about the endlessrestraining cord 22,

. the cord being smaller in circumference than the bottom of thecontainer so thata liquid in the container presses outwardly against themarginal wall and tensions somewhat layer 14 by the cord-restrainedmargin. The retaining ring being of smaller circumference than the bodyof the liquid in the container, this will prevent the outer marginalwall from being drawn outwardly and upwardly. When it is desired toremove the inner tube 20, as for storage of the container or repair ofthe inner tube, the liquid may be removed from the container andthereafter the corded margin of the outer layer of the marginal wall maybe slid over the inner wall, or in other words, bottom 10 of thecontainer may be grasped and pulled through the opening in therestraining band 15 so that the tube may be readily removed.

This construction permits use of a separate inner tube without thenecessity of employing buttons, snap fasteners, lacing, or othercumbersome and expensive fastener means for retaining it. Slow leaks inthe inner layer 13 of the wall will drain without unfastening themarginal wall, and storage of the container when not in use will befacilitated.

Variation may be made without departing from the scope of the inventionand as it is defined by the following claims.

I claim:

1. A collapsible container for liquid comprising a bottom, a marginalWall thereabout and secured thereto, said wall comprising adouble-walled construction of flexible sheet material extending oversaid bottom and providing a pocket between the inner and outer portionsof the wall, an inflatable inner tube removably posimaintaining saidinner and outer portions of the wall in enclosing relation about saidtube. j

2. A collapsible container for liquid comp-rising'a bottom member offlexible material, a marginal wall extending upward and inwardly of themargin thereof and then returning outwardly and downwardly over itselfto the bottom of the container to provide a buoyant pocket for floatingthe wall upon a liquid within the container, an inflatable inner tuberemovably positioned within said pocket at the upper margin of the wall,and means for retaining the downwardly extending portion of the wall atsaid bottom, said retaining means comprising a restraining membersecured to the lower margin of the downwardly extending portion andunderlying said bottom and defining an opening of smaller area than thebottom, the diflerence in area between the bottom and said openingproviding the sole means for maintaining the marginal wall portion inenclosing relation about said tube.

3. A collapsible container for liquid comprising a flat circular bottommember of flexible impervious material, a marginal wall of flexibleimpervious material secured about said bottom and extending upwardly andinwardly therefrom above said bottom member, said wall comprising innerand outer wall members secured to each other at the upper margin of saidwall and defining an annular pocket open at the bottom thereof, aninflatable inner tube removably positioned in said pocket for buoyantlysupporting said wall above a liquid in the container and means forremovably securing the outer wall member about said bottom member, saidsecuring means comprising a flexible endless member smaller incircumferences than said bottom and secured to said outer wall member ata position underlying said bottom member, the difference incircumference of said flexible endless member and the margin of thebottom member providing the sole means for maintaining the inner andouter wall members in enclosing relation about said tube.

4. In a collapsible container having a flexible bottom, a marginal wallthereabout formed with an inner flexible member and an outer flexiblemember which define between them a pocket at the rim of the container,and an inflatable tube in the pocket for buoyantly supporting one rim ofthe wall on the liquid within the container, the improvement whichcomprises an outer flexible wall member which extends from the rim tothe bottom of the container and which terminates at an edge spacedinwardly from and underlying the margin of the bottom, and an endlessrestraining cord secured to said edge of the outer wall and extendingunder the bottom to define an opening of smaller area than the bottom,the difference between the area of said opening defined till by the cordand the area of the bottom being the sole means for maintaining theouter flexible wall member in enclosing relation about said tube.

5. A collapsible container for liquid comprising a bottom of flexiblesheet material, a marginal wall of flexible sheet material around thebottom to retain liquid and having an upper portion forming the rim ofthe container, the wall including an inner flexible member secured tothe margin of the bottom and extending upwardly to the rim and an outerflexible member extending downwardly from the rim to the margin of thebottom of the container to define a pocket between the inner and outermembers, the outer member removably engaging the margin of the bottomand extending around said margin to the underside of the bottom andterminating on the underside of the bottom at an edge which defines anopening of smaller area than the bottom, the difference between the areaof said opening defined by said edge of the outer member and the area ofthe bottom being the sole means for maintaining the outer flexible wallmember in the aforesaid position relative to the inner flexible member.

6. A collapsible container for liquid comprising a flat bottom sheet ofthin flexible sheet material impervious to the liquid to be received inthe container, and a continuous wall of thin flexible sheet materialextending peripherally around the bottom sheet at the margin thereof,the wall including a first wall portion extending upwardly from saidmargins and inwardly over the bottom sheet and terminating at a narrowportion which defines a rim opening for the container of smaller areathan the bottom and a second wall portion flaring outwardly from saidrim opening and terminating at a wide portion which defines an openingsubstantially equal in area to the area of the bottom, a third wallportion projecting inwardly from said wide portion of the second portionto a terminal edge which defines an opening of smaller area than thebottom, said narrow portion of the wall being adapted to receive aninflatable tube in encircling relation and said bottom sheet and saidfirst and second wall portions being adapted to be folded through saidopening defined by said terminal edge of the third portion and then thebottom sheet flattened in face-to-face contact with said third portionto form a pocket between said first and second wall portions forenclosing said tube, the difference in area between said bottom and saidopening defined by the terminal edge being the sole means of maintainingsaid first and second wall sections in enclosing relation about saidtube.

References Cited in the file of this patent UNITED STATES PATENTS1,961,061 McCulloch May 29, 1934 2,084,236 Babb June 15, 1937 2,123,327Biberthaler July 12, 1938 2,505,845 Alvarez May 2, 1950 2,551,673Hasselquist May 8, 1951 I FOREIGN PATENTS 22,301 Great Britain Feb. 19,1903

